90 N/A

car drives fine, can take it up to about 130 mph no problem, it runs strong. its crusing thats not working right.

only between 2500-3500 rpm at STEADY throttle ONLY, car starts bucking pretty bad.

im running mazda trix's true dual exaust, so i have two seperate pipes the whole way back. i installed 2 haltech A/F guages, one on eash header piep so i can get a separate a/f reading off each rotor.

now at 2500-3500 rpm, i watch the fuel practically lean its way off the meter until i get no reading on either rotor. then it starts to buck until i tap the throttle. also, once the fuel goes off the meter, it throws me a throttle sensor narrow, throttle sensor full range and a fe4ed back code (from the lack of fuel).

i replaced that damn tps not even 2 years ago. both o2 sensors are new, as are just about every other sensor in the car, i systematically replaced every one once i reached 100K miles.

do you think the tps went bad already, are mazdatrix's replacment tps's ****? im do have the factory service test lights tool to test the tps.

heres something wierd. i used to always get the one light to go on, like how the fsm tells you to set the tps, but the light was always the GREEN one, as it is on everyone's car i use the tool to set. only now, yea im still getting just one light to go on, but its the red one. and on another car, when only the red light came on too, the car doesnt seem to run fine. i can use my DMM to get the sensor at barely 0.9 V, but it likes to stay only around 0.845 or so, wont go to 1.0 and stay there.

if not the tps, do you think the fuel pump is getting ready to take a ****? i need to know why the fuel slowly cuts out until it practally gets none at crusing speeds.

 

does it only do it when the car is in gear or does it hesitate or spuder when you just give it gas at 3000 rpm. I wouldn't think that it would be the fuel pump because why would it just buck at certain rpms.

 

Two things:

Is the TPS adjusted correctly? This is almost always caused by a misadjusted/bad TPS.

Uh, the car only has one O2 sensor.

 

Fuel filter??

 

It looks like he has 2 O2 sensors.

I'll bet the ECU is seeing rich even as the AF goes lean.
When he blips the throttle, the ECU goes back to it's map, then, after no throttle change tries closed loop again.

I suggest wiring the 2 sensors to a cross-over wired DPDT toggle switch, so the ECU sees one sensor while the AF gage sees the other.

Also check the ECU's grounds.

Maybe sell me the spare AF gage.